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You cross true breeding ppqqrr with true breeding ppqqrr. you then do a testcross. if 2000 progeny are produced from the test cross how many individuals do you expect inn the clas pqr

A. 750 Individuals
B. 1000 Individuals
C. 1250 Individuals
D. 1500 Individuals

User Mr Shoubs
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1 Answer

4 votes

Final answer:

All progeny from a cross between true breeding ppqqrr individuals will be homogeneous ppqqrr. No expected number of individuals in another genotypic class applies since all offspring have the same genotype and there would be no segregation into different classes. Therefore , the correct answer options is c)

Step-by-step explanation:

When a cross is made between two true breeding ppqqrr individuals, all of the progenies will be ppqqrr. A testcross typically involves crossing an individual with a homozygous recessive individual, and in this case, since the progeny are already homozygous recessive, the testcross would result in all offspring being ppqqrr.

Hence, no matter how many progenies are produced from the testcross, they would all be the same genotype ppqqrr, rendering the classes 'pqr' irrelevant because all progenies are of one class.

Therefore, none of the options A. 750 Individuals, B. 1000 Individuals, C. 1250 Individuals, D. 1500 Individuals apply here because the progeny would not segregate into different classes. This is consistent with Mendelian genetics, particularly the inheritance of recessive traits.

User Halayem Anis
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